console.log({} === {})
let a = b ={};
console.log(a == b)
var obj = {
    valueOf() {
        return 1
    }
}
console.log(obj == 1)
console.log([1] == 1)
console.log(false == '0')
console.log('' == '0')  // 
console.log(true == [])
console.log([] == {})
console.log([] == ![])  
Number(undefined)            // NaN
// Number(Symbol('s'))          // TypeError...
console.log(Number([]),Number({}),Number(""))